Degradation of Recalcitrant Organics in Oil Sands Process Water (OSPW) Using Combined Electro-Oxidation and Electrochemically Activated Peroxymonosulfate (EO-PMS)

• Author / Creator

  Abdelrahman, Ali Satti Abdellatif

• In northern Alberta, the bitumen extraction process from oil sands ores consumes large amounts of water, resulting in the generation of huge volumes of oil sand process water (OSPW). Currently, the treatment of OSPW is considered a major challenge facing the oil sands industry. Moreover, among the different constituents in OSPW, naphthenic acids (NAs) have attracted increasing attention due to their acute toxicity associated with complexity and persistently, which are great hazards towards several organisms. Therefore, great efforts have been made in developing efficient and effective treatment techniques for the remediation of OSPW.
  The main objective of this research was to investigate the applicability and effectiveness of using combined electro-oxidation and electrochemically activated peroxymonosulfate (EO-PMS) process for the treatment of OSPW. In the first stage of this study, the coupled EO-PMS process showed high removal efficiency of 5-Phenylvaleric Acid (PVA) as a NA model compound, in which EO was enhanced by the successful electrochemical activation of PMS at different electrodes surface. The removal efficiencies increased with the increase in the PMS concentration and applied current, however, decreased at higher levels. Both sulfate radicals (SO4•‾) and hydroxyl radicals (•OH) were found to be the primary reaction oxidants for PVA degradation. A complete removal of 50 mg/L PVA was achieved within 1 h under optimal conditions of carbon felt (cathode), platinum Pt (anode), PMS = 4mM, and current I= 250 mA. In the second stage of this study, the combined EO-PMS process using Pt, dimensionally stable anodes (DSA), boron-doped diamond (BDD), and graphite plate anodes and carbon felt used as cathode was able to reduce the classical and oxidized NAs as well as aromatics in OSPW. Applying the EO only showed lower removal of NAs compared when adding PMS to the system using the same Pt anode. DSA, BDD and graphite plate anodes achieved higher reduction of 76%, 88.4% and 89.7% of classical NAs (O2-NAs) concentration, respectively, while only BDD was able to completely remove all the oxidized NAs. The combined system of EO-PMS presents an efficient technology for the degradation of NAs and has a great potential to be attractive for wastewater treatment in oil sands industry due to its flexibility and high effectiveness at removing constituents of concern from OSPW as part of reclamation approaches.

• Subjects / Keywords

  • Electro-oxidation
  • Electrochemical activation of PMS
  • OSPW
  • Naphthenic acids
  • Peroxymonosulfate
  • Sulfate radical
  • Hydroxyl radical

• Graduation date

  Fall 2021

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-j7pr-9590

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.